See Update Below.
Well here's an idea that must have sounded good at one point. Upstart online brokerage Zecco (already known for pulling attention-grabbing stunts) had the bright idea for April Fool's Day to load up users' balances with much more money than they actually had
-- sometimes millions more. Except... it looks like they never bothered to make sure people couldn't use that money. So plenty of users started making trades with the fake money... and when Zecco realized it, the company apparently started to force sell, even at a loss, charging the losses to the customers along with
a "$19.99 broker-assisted trading fee." Oops. Update
: Consumerist has updated their post with a message from Zecco claiming that it was not an April Fool's joke, but noting "Some clients may experience incorrect display of Buying Power and Account Balances." It's not entirely clear how those "incorrect displays" were apparently off by millions in some cases. Update 2
: Zecco is again insisting this was not an April Fool's joke
and that it was "a bad feed" from a vendor. It's not entirely clear why it took the firm 5 days to explain that, however...